Cartridge inserts are used to allow a firearm owner to use different sized cartridges for similar caliber bullets with a particular firearm. The cartridge inserts are nonpermanent attachments to a firearm's barrel. Inserts can be used for rifles, shotguns, and pistols. The most common cartridge conversion inserts alter the length of the bullet cartridge used within the firearm. For example, a .32 automatic colt pistol bullet cartridge can be inserted into a .303 caliber insert. A .303 rifle can then fire the loaded .303 caliber insert. Problems with these types of cartridge inserts include the bullet not securely remaining inside the insert and the insert deforming over time. In addition, use of these conventional cartridge inserts causes an increased inefficiency when loading a firearm.